c#课件：网段扫描

using System;
using System.Net;
using System.Threading;
using System.Windows.Forms;

namespace 网段扫描程序{
   public partial class frmMain:Form{
       public frmMain(){
           InitializeComponent();
       }
       private void frmMain_Load(object sender,EventArgs e){}

       private void button1_Click(object sender,EventArgs e){
           IPHostEntry myHost = new IPHostEntry();
           try{
               // Dns.GetHostName()获取本地计算机的主机名
               // Dns.GetHostByName()获取指定 DNS 主机名的 DNS 信息
               //得到本地主机的DNS信息

               myHost = Dns.GetHostByName(Dns.GetHostName());

               //显示本地主机名
               textBox1.Text = myHost.HostName.ToString();

               //显示本地主机的IP地址表
               for (int i = 0;i <myHost.AddressList.Length;i++){
                   string ip = myHost.AddressList[i].ToString();
                   richTextBox1.AppendText("本地主机IP地址->"+ ip + "\r");
               }
           }catch (Exception error){
               MessageBox.Show(error.Message);
           }
       }

       private void button2_Click(object sender,EventArgs e){
           IPHostEntry myDnsToIP = new IPHostEntry();
           //Dns.Resolve 方法:将 DNS 主机名或以点分隔的四部分表示法格式的 // IP 地址解析为 IPHostEntry实例
           myDnsToIP = Dns.Resolve(textBox2.Text.ToString());
           //显示此域名的IP地址的列表
           for (int i = 0;i <myDnsToIP.AddressList.Length;i++){
               richTextBox1.AppendText(textBox2.Text + "的IP地址是"+ myDnsToIP.AddressList[i].ToString() + "\r");
           }
       }

       private void button3_Click(object sender,EventArgs e){
           richTextBox1.Clear();
           //Thread 类:创建并控制线程
           Thread thScan = new Thread(new ThreadStart(ScanTarget));
           //Thread.Start 方法:启动线程
           thScan.Start();
       }

       private void ScanTarget(){
           //构造IP地址的31-8BIT 位，也就是固定的IP地址的前段

           // numericUpDown1是定义的System.Windows.Forms.NumericUpDown控件

           string strIPAddress = numericUpDown1.Text + "."+ numericUpDown2.Text + "."+ numericUpDown3.Text + ".";
           //开始扫描地址
           int nStrat = Int32.Parse(numericUpDown4.Text);
           //终止扫描地址

           int nEnd = Int32.Parse(numericUpDown5.Text);
           //扫描的操作
           for (int i = nStrat;i <= nEnd;i++){
               string strScanIPAdd = strIPAddress + i.ToString();
               //转换成IP地址
               IPAddress myScanIP = IPAddress.Parse(strScanIPAdd);
               try{//你可以加入自已的,增强功能

                   // Dns.GetHostByAddress 方法:根据 IP 地
                   //址获取 DNS 主机信息。
                   IPHostEntry myScanHost =
                   Dns.GetHostByAddress(myScanIP);
                   //获取主机的名
                   string strHostName = myScanHost.HostName.ToString();
                   SetRichBoxTxt(strScanIPAdd + "->"+ strHostName + "\r");
               }catch (Exception error){
                   MessageBox.Show(error.Message);
               }
           }
       }
       delegate void SetTextCallback(string text);

     &nbs p; private void SetRichBoxTxt(string text){
           if (this.richTextBox1.InvokeRequired){
               SetTextCallback d = new SetTextCallback(SetRichBoxTxt);
               this.Invoke(d,new object[]{text});
           }else{
               this.richTextBox1.Text = text;
           }
       }
   }
}